Chloride Salt Effects on Algal Populations And the Dangers that they Present By:Brandon Perrotte Central Catholic 2008

Introduction Chloride salts have potentially harmful effects on algae. These salts enter the ecosystem due to runoff. They prove to be corrosive and harmful to the environment. The chloride salts, when used cause the decrease in population of thousands of organisms, especially algae. This would therefore affect the organisms that feed off of the algae and would then disrupt the environment.

Background Information: Chloride Salts Chloride Salts are binary compounds of chlorine. They can be corrosive and are soluble in water. The salts used in the experiment were sodium, magnesium and calcium chloride. Some solid chlorides can be decomposed through the process of hydrolysis.

Environmental Effects and Inhibitions of Chloride Salts We use sodium chloride, or common road salt, to clear the ice from our streets as to prevent accidents and injury. This act is also inducing runoff into small marine and wildlife ecosystems as the wheels of cars push them into the soil and into streams and rivers. The runoff contains harmful chemicals. This is harmful to thousands of small organisms and their habitat. It also in low proportion gives a low toxicity level to the water that we drink and use for common practices such as brushing our teeth and showering daily.

Chloride Levels in Streams Minnesota passed laws restricting salt use for its disruptive corrosion and for the reduction of water pollution

Discriminative Algal Traits Euglena It is a common protist and functions in sunlight. It is commonly cylindrical in shape. The chloroplasts in euglena are clear. The paraflagellar that controls light absorption monitors light shields the photoreceptor. The algae can function without sunlight by taking nutrients from decomposed organisms. Chlamydomonas Chlamydomonas are unicellular flagellates. They operate on sunlight as a photosynthetic plant. The ion channels such as channelrhodopsin are activated by light.

Purpose The Purpose of this experiment is to identify the potentially harmful effects of chloride salt concentrations on two different algal populations.

Hypothesis The null hypothesis in this experiment states that the chloride salts will not increase the population of algae and possibly present dangerous circumstances for the remaining population.

Materials and Methods Materials Borosilicate test tubes(72) Spectrophotometer(1) Fluorescent lamp(1) A large container of spring water 2(?)mL containers of both euglena and chlamydomonas. 5ml pipette 200 microliter pipette Three containers of sodium chloride, magnesium chloride, and calcium chloride. Test Tube Racks(2) One Sharpie marker Micropipette and pipette tips General Experimentation Six sets of test tubes were filled with different concentrations of water, algae, and a variable. They were placed in a test tube rack and were given light by an overhanging fluorescent lamp. A spectrophotometer was used and set at a blue-green wavelength(503nm). The tubes were then placed into the spectrophotometer and tested every three days five times.

Procedure 1.36 borosilicate test tubes were placed in both test tube racks tubes were placed into each row. 3.The top of each test tube was marked with a Sharpie marker to indicate the placement of the tube in the spectrophotometer. 4.The tubes were then filled with different concentrations of algae, spring water, and one of three chloride salts. Pipettes with assigned tips. 2ml of algae was the constant amount. The pipettes must never cross-contaminate between chloride salts and algal species. 5.Concentrations of the stock solution were divided as 0%, 10%, and 40%. Four tubes in each row were designated to contain one of the three concentrations.

Procedure (Continued….) 6. The control group in the experiment was a group of six tubes that contained 3ml of algae(60%) and 2ml of algae(40%) without adding any of the variable. 7. In the first set of 36 test tubes euglena was mixed in concentration with sodium chloride, magnesium chloride, and calcium chloride. They were divided into sets of twelve tubes assigned to each variable. 8. The same procedure was done as in step 7 only replacing euglena with chlamydomonas as the algal population being affected by the chloride salts. 9. Once all solution has been inserted into the test tubes, the tubes are then taken out of the test tube rack and placed into the spectrophotometer at the mark made earlier in the experiment by the Sharpie marker. Absorption readings are then taken. These are taken to indicate the effect of the different concentrations of chloride salts on algal populations. 10. Step 9 was repeated every three days for fifteen days while the light of the fluorescent lamp remained constantly over the tubes. Readings were then recorded and analyzed in an ANOVA statistical analysis.

ANOVA From the results of the ANOVA’S conducted a p- value graph was created and it is shown below. The increments in the legend compare both concentrations of the chloride salts used.

Resulting Graphs and Information The charts below rely on the average absorbency of light by the algal populations of chlamydomonas and euglena.

Conclusive Effects of the Chloride Salts on algae The chloride salts had a negative long term effect on the algal populations of both euglena and chlamydomonas. This may have been due to the corrosive properties of the salts or it may have been just the concentration of the salt that it that made up its habitable environment or in this case inhabitable environment. Referring to the graphs of average absorbency on the previous page the algae thrived when there was not a very high concentration of salts.

Potential Harm To Environmental Algae These results show that algal populations in the environment are at a great risk of decreasing in size because of the potential abuse and misuse of chloride salts. The communities at the greatest risks are the ones near roadsides where road salts are being used to clear ice for safety. This effects many environmental organisms and ultimately the ecosystem that the algae made up.

Conclusion It is concluded in this experiment that the decrease in the algal populations was due to the chloride salts inhibition of growth. The chloride salts at a higher concentration killed masses of algae and caused them not to grow back. This shows potential for the same happenings in the surrounding environment.

Extensions Some extensions that could have improved the quality and obvious depth and extensiveness of this experiment is the use of more tubes in the experiment and the use of different concentrations. Some mistakes made in this experiment was the misplacement of the test tubes in the spectrophotometer instead of being placed in the same position of every time. The same results were found twice in two testing trials as well.

Works Cited